Field of the Invention
This invention relates to an improved incubation structure for incubating large quantities of eggs. More particularly, this invention concerns an incubator which maintains the internal environmental consistency and the egg capacity of present systems while vastly reducing the floor space required for the unit. Additionally, this invention concerns an improved incubator structure which simplifies assembly, construction and servicing and further facilitates increasing overall capacity by providing means for simplifying the ability to share common side walls between separate incubation structures.
At the present time, an increasing demand exists to feed an expanding world population. Moreover, scientific studies have confirmed the beneficial results obtained by a person consuming less red meat. One viable solution to these problems lies in the mass production of poultry as food such as chicken and turkey. Integral to this solution is the ability to efficiently incubate and hatch mass quantities of poultry eggs. Incubation systems for this purpose, of course, have been used in hatcheries for many years. However, in order to meet the demand associated with mass production, incubation structures and incubators in general have grown to enormous proportions. The size of these incubators has created a practical problem with respect to the cost associated with these large units in proportion to the number of eggs which can be handled. Accordingly, it is desirable to provide an incubation system which is reduced in size in comparison to contemporary units while maintaining current capacity. Moreover, it is equally desirable to design these incubators for easier assembly and serviceability than is presently available.
The invention not only reduces the present size of incubators but simplifies construction and serviceability and further permits the addition of more units by providing a structure which permits the joining of subsequent incubators to a shared or common side wall with existing units. Besides decreasing floor space, this design also decreases the cost associated with expansion and results in a lower cost product for the consumer.
Both previous incubators and those of the present invention are formed from multiple wall and ceiling panels joined together in a rectangular configuration. Double doors are provided at each short end of the unit for loading or unloading the large racks which house the eggs during the incubation process. Additionally, the floor of the incubation chamber is provided with channeled or V-grooved tracks for easier handling and movement of the egg racks through the chamber. Depending on the circumstances, an actual floor containing these racks may be installed with the incubator or the tracks may be affixed to the floor of the hatchery in which the incubator is constructed. Nevertheless, previous incubation structures fail in many respects to reduce critical floor space requirements and decrease the time and labor costs associated with assembly, construction and serviceability of these incubators.
The first problem cognizant in previous systems concerns the assembly of both the initial incubation structure and additional structures or units subsequently purchased. Typically, adjacent side wall and ceiling panels were joined together by riveting "L" shaped aluminum extrusions along both the interior and exterior corners formed by these overlapping panels. This was a time and labor consuming assembly which required the exterior and interior corner extrusions to be installed separately and further required the installer to first drill holes in the extrusions and panels before the rivets could be applied. Moreover, when a second unit was acquired, this construction inhibited the second unit from sharing a common side wall with the original unit because there was not a convenient way to join the new ceiling panels of the second unit to the existing side wall and ceiling panels of the original unit. While the two incubator units could be joined to share a common wall, it was a labor and time consuming process. Consequently, even though the two incubation structures were constructed side by side, the second unit frequently did not adopt a common side wall with the original structure but retained both side walls for assembly. With the present invention, a single corner extrusion is employed which not only simplifies assembly of the original incubation structure but which further promotes the cost saving feature of sharing common side walls with subsequently installed incubation structures.
A second problem in previous incubation systems concerns the large space required in order to provide proper environmental conditions for the large number of eggs undergoing incubation. Generally, racks holding over 7,500 eggs are rolled into the incubation chamber through the double doors at the loading or front end of the chamber. A large incubator will hold 12 racks in side by side configuration forming two rows of six racks. As the racks of fully gestated eggs are removed from the exit end of the incubator, racks containing new eggs are loaded at the loading end of the chamber. Accordingly, there is a continuous progression of racks housing eggs at various stages of gestation through the incubator so that the oldest eggs are always closest to the exit end of the incubation chamber.
In order to maintain stable environmental conditions, previous incubators required a large space between the loading end of the incubator and the closest egg racks. This space was necessary for the internal air to thoroughly mix with the air drawn into the chamber from outside. Specifically, an air intake vent, positioned directly over the loading doors, provided means for drawing fresh air into the chamber. Because the chamber is maintained at a higher temperature than the air in the hatchery housing the incubator, natural convection caused the cooler outside air to travel into the vacant space and mix with the heated and humidified air in the chamber. Since the cool outside air was randomly mixed with the inside air a large mixing area was needed to assure thorough and complete mixing. Directly above the first pair of racks, attached to the ceiling, were a series of fans and means for heating and humidifying the internal air. The fans would circulate the air over the heating and humidifying elements and then over the tops of the racks to the rear or exit end of the chamber. At the same time the fans draw the heated and humidified air from the rear of the chamber across the eggs in the racks. Additionally, warm air and carbon dioxide produced by the older eggs would be combined with the heated and humidified air from the rear of the chamber to warm the newer eggs in the front of the chamber. The cycle was completed when the air being drawn across the eggs returned to the space at the loading end of the chamber to mix with the cool air entering through the air intake and descending toward the floor of the air mixing space. It was also necessary to provide an exhaust opening in the ceiling at the rear of the chamber so that air pressure inside the incubator remained stable.
Removing the necessary mixing space at the front of the chamber would effectively reduce the floor space covered by the incubator. However, under such reduced space conditions, the cool external air entering the chamber and traveling down the front end wall would flow directly onto the newest eggs. This would create an extremely unstable environment which would reduce the number of embryos that would grow and mature. Additionally, under this reduced space arrangement, the air intake vent would be adjacent the air distribution fans and this proximity would disrupt the critical air circulation and stability of the internal environment. The fans would simply draw outside air into the chamber and directly to the fans preventing the complete mixing achieved when the front air space was present. The present invention overcomes the problem associated with removing the air mixing space at the front of the chamber by attaching a three-sided vertical channel to the air intake so that the open side of the channel faces the loading or front end wall. This prevents the cool external air from immediately being drawn into the fans and further positively controls the flow of cool air into the chamber. Importantly, the channel is also spaced a small distance from the end wall so that some cool air can escape around the side of the channel as the cool air sinks to the floor of the chamber. Consequently, this structure creates an even, positive mixture of the escaping cool air with the warm, humidified air returning across the eggs under circulatory effects of the ceiling fans.
A third problem existent in previous systems was the difficulty inherent in installing and servicing the electrical system of the incubator. Particularly, for safety reasons, the wiring for the air distribution fans and heating elements were housed inside a protective channel screwed to the ceiling of the incubator. Consequently, for both installation and service, an electrician would be required to remove this protective enclosure and perform the necessary service while balancing on a ladder. Moreover, servicing the electrical system after the incubator was operating placed the electrician in the same awkward position of having to work over his head and additionally placed the eggs in close proximity thereby raising a potential for damaging the eggs as well as disrupting the internal environment of the incubator by having the doors opened or the electrician present to do repairs. The present invention overcomes this dual problem by employing an aluminum extrusion designed for placement between ceiling panels which has means on its bottom surface for attaching the series of air distribution fans and which also has a internal channel, accessible from the top of the roof of the incubator itself, for housing the electrical outlets and wiring for the fans and heating elements. Accordingly, during installation, the wiring for these elements can be done on the incubator roof and the fans and heating elements can simply be plugged into the electrical outlets on the bottom surface of the ceiling extrusion.